<?php

// +----------------------------------------------------------------------

// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]

// +----------------------------------------------------------------------

// | Copyright (c) 2007 http://thinkphp.cn All rights reserved.

// +----------------------------------------------------------------------

// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )

// +----------------------------------------------------------------------

// | Author: liu21st <liu21st@gmail.com>

// +----------------------------------------------------------------------

namespace Think\Db\Driver;

use Think\Db;

defined('THINK_PATH') or exit();

/**

 * Mysqli数据库驱动类

 */

class Mysqli extends Db{



    /**

     * 架构函数 读取数据库配置信息

     * @access public

     * @param array $config 数据库配置数组

     */

    public function __construct($config=''){

        if ( !extension_loaded('mysqli') ) {

            E(L('_NOT_SUPPERT_').':mysqli');

        }

        if(!empty($config)) {

            $this->config   =   $config;

            if(empty($this->config['params'])) {

                $this->config['params'] =   '';

            }

        }

    }



    /**

     * 连接数据库方法

     * @access public

     * @throws ThinkExecption

     */

    public function connect($config='',$linkNum=0) {

        if ( !isset($this->linkID[$linkNum]) ) {

            if(empty($config))  $config =   $this->config;

            $this->linkID[$linkNum] = new \mysqli($config['hostname'],$config['username'],$config['password'],$config['database'],$config['hostport']?intval($config['hostport']):3306);

            if (mysqli_connect_errno()) E(mysqli_connect_error());

            $dbVersion = $this->linkID[$linkNum]->server_version;

            

            // 设置数据库编码

            $this->linkID[$linkNum]->query("SET NAMES '".C('DB_CHARSET')."'");

            //设置 sql_model

            if($dbVersion >'5.0.1'){

                $this->linkID[$linkNum]->query("SET sql_mode=''");

            }

            // 标记连接成功

            $this->connected    =   true;

            //注销数据库安全信息

            if(1 != C('DB_DEPLOY_TYPE')) unset($this->config);

        }

        return $this->linkID[$linkNum];

    }



    /**

     * 释放查询结果

     * @access public

     */

    public function free() {

        $this->queryID->free_result();

        $this->queryID = null;

    }



    /**

     * 执行查询 返回数据集

     * @access public

     * @param string $str  sql指令

     * @return mixed

     */

    public function query($str) {

        $this->initConnect(false);

        if ( !$this->_linkID ) return false;

        $this->queryStr = $str;

        //释放前次的查询结果

        if ( $this->queryID ) $this->free();

        N('db_query',1);

        // 记录开始执行时间

        G('queryStartTime');

        $this->queryID = $this->_linkID->query($str);

        // 对存储过程改进

        if( $this->_linkID->more_results() ){

            while (($res = $this->_linkID->next_result()) != NULL) {

                $res->free_result();

            }

        }

        $this->debug();

        if ( false === $this->queryID ) {

            $this->error();

            return false;

        } else {

            $this->numRows  = $this->queryID->num_rows;

            $this->numCols    = $this->queryID->field_count;

            return $this->getAll();

        }

    }



    /**

     * 执行语句

     * @access public

     * @param string $str  sql指令

     * @return integer

     */

    public function execute($str) {

        $this->initConnect(true);

        if ( !$this->_linkID ) return false;

        $this->queryStr = $str;

        //释放前次的查询结果

        if ( $this->queryID ) $this->free();

        N('db_write',1);

        // 记录开始执行时间

        G('queryStartTime');

        $result =   $this->_linkID->query($str);

        $this->debug();

        if ( false === $result ) {

            $this->error();

            return false;

        } else {

            $this->numRows = $this->_linkID->affected_rows;

            $this->lastInsID = $this->_linkID->insert_id;

            return $this->numRows;

        }

    }



    /**

     * 启动事务

     * @access public

     * @return void

     */

    public function startTrans() {

        $this->initConnect(true);

        //数据rollback 支持

        if ($this->transTimes == 0) {

            $this->_linkID->autocommit(false);

        }

        $this->transTimes++;

        return ;

    }



    /**

     * 用于非自动提交状态下面的查询提交

     * @access public

     * @return boolen

     */

    public function commit() {

        if ($this->transTimes > 0) {

            $result = $this->_linkID->commit();

            $this->_linkID->autocommit( true);

            $this->transTimes = 0;

            if(!$result){

                $this->error();

                return false;

            }

        }

        return true;

    }



    /**

     * 事务回滚

     * @access public

     * @return boolen

     */

    public function rollback() {

        if ($this->transTimes > 0) {

            $result = $this->_linkID->rollback();

            $this->_linkID->autocommit( true);

            $this->transTimes = 0;

            if(!$result){

                $this->error();

                return false;

            }

        }

        return true;

    }



    /**

     * 获得所有的查询数据

     * @access private

     * @param string $sql  sql语句

     * @return array

     */

    private function getAll() {

        //返回数据集

        $result = array();

        if($this->numRows>0) {

            //返回数据集

            for($i=0;$i<$this->numRows ;$i++ ){

                $result[$i] = $this->queryID->fetch_assoc();

            }

            $this->queryID->data_seek(0);

        }

        return $result;

    }



    /**

     * 取得数据表的字段信息

     * @access public

     * @return array

     */

    public function getFields($tableName) {

        $result =   $this->query('SHOW COLUMNS FROM '.$this->parseKey($tableName));

        $info   =   array();

        if($result) {

            foreach ($result as $key => $val) {

                $info[$val['Field']] = array(

                    'name'    => $val['Field'],

                    'type'    => $val['Type'],

                    'notnull' => (bool) ($val['Null'] === ''), // not null is empty, null is yes

                    'default' => $val['Default'],

                    'primary' => (strtolower($val['Key']) == 'pri'),

                    'autoinc' => (strtolower($val['Extra']) == 'auto_increment'),

                );

            }

        }

        return $info;

    }



    /**

     * 取得数据表的字段信息

     * @access public

     * @return array

     */

    public function getTables($dbName='') {

        $sql    = !empty($dbName)?'SHOW TABLES FROM '.$dbName:'SHOW TABLES ';

        $result =   $this->query($sql);

        $info   =   array();

        if($result) {

            foreach ($result as $key => $val) {

                $info[$key] = current($val);

            }

        }

        return $info;

    }



    /**

     * 替换记录

     * @access public

     * @param mixed $data 数据

     * @param array $options 参数表达式

     * @return false | integer

     */

    public function replace($data,$options=array()) {

        foreach ($data as $key=>$val){

            $value   =  $this->parseValue($val);

            if(is_scalar($value)) { // 过滤非标量数据

                $values[]   =  $value;

                $fields[]   =  $this->parseKey($key);

            }

        }

        $sql   =  'REPLACE INTO '.$this->parseTable($options['table']).' ('.implode(',', $fields).') VALUES ('.implode(',', $values).')';

        return $this->execute($sql);

    }



    /**

     * 插入记录

     * @access public

     * @param mixed $datas 数据

     * @param array $options 参数表达式

     * @param boolean $replace 是否replace

     * @return false | integer

     */

    public function insertAll($datas,$options=array(),$replace=false) {

        if(!is_array($datas[0])) return false;

        $fields = array_keys($datas[0]);

        array_walk($fields, array($this, 'parseKey'));

        $values  =  array();

        foreach ($datas as $data){

            $value   =  array();

            foreach ($data as $key=>$val){

                $val   =  $this->parseValue($val);

                if(is_scalar($val)) { // 过滤非标量数据

                    $value[]   =  $val;

                }

            }

            $values[]    = '('.implode(',', $value).')';

        }

        $sql   =  ($replace?'REPLACE':'INSERT').' INTO '.$this->parseTable($options['table']).' ('.implode(',', $fields).') VALUES '.implode(',',$values);

        return $this->execute($sql);

    }



    /**

     * 关闭数据库

     * @access public

     * @return volid

     */

    public function close() {

        if ($this->_linkID){

            $this->_linkID->close();

        }

        $this->_linkID = null;

    }



    /**

     * 数据库错误信息

     * 并显示当前的SQL语句

     * @static

     * @access public

     * @return string

     */

    public function error() {

        $this->error = $this->_linkID->errno.':'.$this->_linkID->error;

        if('' != $this->queryStr){

            $this->error .= "\n [ SQL语句 ] : ".$this->queryStr;

        }

        trace($this->error,'','ERR');

        return $this->error;

    }



    /**

     * SQL指令安全过滤

     * @static

     * @access public

     * @param string $str  SQL指令

     * @return string

     */

    public function escapeString($str) {

        if($this->_linkID) {

            return  $this->_linkID->real_escape_string($str);

        }else{

            return addslashes($str);

        }

    }



    /**

     * 字段和表名处理添加`

     * @access protected

     * @param string $key

     * @return string

     */

    protected function parseKey(&$key) {

        $key   =  trim($key);

        if(!preg_match('/[,\'\"\*\(\)`.\s]/',$key)) {

           $key = '`'.$key.'`';

        }

        return $key;

    }

}

